While a display screen is operating normally, a source driver chip (also referred as a source IC) provides a corresponding display signal to each data line according to an operating mode of the display screen, so that each pixel unit in the display screen may receive the display signal provided on the data line corresponding to the pixel unit, and thus an image is displayed normally. However the display signal provided by the source IC may become abnormal due to a damage of the source IC, or another reason, so that the display signals provided on the respective data lines may be disordered, and thus the image may be displayed abnormally on the display panel, thus degrading a display effect thereof.